Hydraulically controlled apron and ejector assembly for earth working scrapers



Sept. 9, 19 D. E. MURRAY HYDRAULICALLY CONTROLLED APRON AND EJECTOR ASSEMBLY FOR EARTH WORKING SCRAPERS 3 Sheets-Shec 1 Filed Dc. 9, 1950 ATTORNEYS Sept. 9, 1952 Filed Dec. 9, 1950 HYDRAULICALLY CbNTROLLED APRON AND EJECTOR E. MURRAY ASSEMBLY FOR EARTH WORKING SCRAPERS 5 Sheets Sheet 2 BY W ATTORNEYS Sept. 9, 1952 D. E. MURRAY 2,609,

HYDRAULICALLY CONTROLLED APRON AND EJECTOR ASSEMBLY FOR EARTH WORKING SCRAPERS Filed Dec. '9, 1950 3 Sheets-Sheet 3 INVENTOR .DonaZdE. Murray ATTORNEYS Patented Sept. 9, 1952 UNITEDFVSTATES PPAHTENTYY oFFice-f HYDRAULICALLY CONTROLLED APRON AND amoroa ASSEMBLY on EARTH WORK- ING SVCRAPERS I DonaldE Murray, Modesto, Calif. Application December 9, 1950, seam, 199,975

4 Claims.

. 1 The present invention relates to an improvement in an earth working scraper, of the carrytype, which includes a bowl'having a forwardly swingable rear endgate, and a vertically adjustable apron cooperating with said bowl at the front.

The major object of this invention is to provide novel control mechanism for actuating the apron and rear endgate in a predetermined sequence; such mechanism including a single power device under the control of the operator, and connections between said power device, apron, and rear endgate arranged to cause said sequential operation.

Another important object of the invention is to provide control mechanism, as in the preceding paragraph, which may be employed to vertically adjust the apron, either up or down, without moving the endgate, or to vertically adjust the apron to full open position followed by forward swinging of said endgate; the respective purposes of such actions appearinghereinafter.

A further object of the invention is to provide acontrolmechanism, for the purpose described, which-includes a hydraulic power cylinder, the actuating. connections for the apron and rear endgate including parts mounted for relative separating motion, and the power cylinder being connected therebetween; the part corresponding to the rear endgate having greater resistance to motion whereby the part corresponding to the apron reacts first to expansion of the cylinder,

so that the apron acts ahead of said rear endgate.

A still further object of the invention is to provide a control mechanism, as above, which is relatively simple in structure, being designed for ease and economy of manufacture, but nevertheless sturdy and capable of withstanding the hard usage to which earth working equipment is' subjected.

An additional object of the invention is to provide a practical and, reliable hydraulically controlled earth working scraper, and yetone ,which wil be exceedingly effective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following v specification and claims.

In the drawings: Fig. 1 is a side elevation of the scraper with thebowl raised to carrying positionpthe front apron being closed and the rearendgate-being retracted.

Fig. 2 is a longitudinal sectional elevation with the parts as in Fig. 1.

Fig. 3 is a similar View, but shows the front apron raised.

Fig. 4 is a similar view, but shows the'front apronraised and the rear endgate advanced.

Fig. 5, is a fragmentary rear end elevation showing the cross shaft assembly as employed between the power'cylinder and the "actuating connections for'the front apron. Referring now more particularly to' the characters of reference on the 'drawings,lthe'. earth working scraper which embodies the present invention is of the type which is adapted to dig, carry, and dump earth. 'suchuscraper includes a bowl, indicated generally at I, supported at-its rear end by transversely spaced, pneumatic tire wheels 2, and carried atits forward end by a yoke 3 pivoted, as at 4, to the bowl for .up and down adjustment of "the latter by means of a double acting, hydraulic power cylinder 5 'connected between the yoke at the front; as at .6, and the front of an overhead frame I, as at'8. The overhead frame 1 is rigid with the 'bowl I whereby the power cylinder 5 is operative to cause raising or lowering of said bowl.

A gooseneck 9 projects in rigid relationforwardly from the yoke 3, being supported. by a pony'truck Ill adapted to be coupled'to a tractor by a draft bar ll. v

. An earth cutting digging blade 12 extends transversely between the side-plates "l3 ofithe bowl I at'the lower edge of said'plates and. at a point intermediate the front and rear of said bowl. 1

A normally retracted but forwardly swingable rear endgate [4, including a bottom portion i5, is disposed between the side plates 13, forming the bottom and back of said bowl; the bottom portion l5 being hinged, as at [6, to the blade l2. The rearend gate' [4 includes, at its rear upper edge, a cross-beam I1, and a stop l8 projects rearwardly from said cross beam H to normally rest on a main cross beam l9- of, the frame structure of the scraper.

' A front apron 20 cooperates with the bowll 3 corresponding sides of the bowl I to pivotal lower end connections, as at 25, with the corresponding ends of radial lever arms 26 which are fixed to and depend from a cross shaft 21.

The cross shaft 21 is disposed rearwardly of the main cross beam l9 and is suitably journaled' in connection with the frame structure of. the

scrapen A third or central, radial lever arm 28 is fixed to the cross shaft 21 and depends therefrom at a generally rearward and downward incline.

Ahead of the central radial lever arm 28,- and in substantially the same vertical longitudinal plane, there is a dependent link 29 pivoted at its upper end, as at 30, to the bottom of the main cross beam 19. A connector link 3| extends forwardly and upwardly in pivotal connection between the lower end of the link 29 and a point on the back side of the rear endgate M; the

points of pivoting being indicated at 32 and 33,

respectively. p

A hydraulic pressure power cylinder, indicated at 34, is pivoted at its rear end, as at 35; to the lower end of the central radial lever arm 28,. and is adjustably pivoted at its. forward end, as at 36,,to' the depending link 29.; The power cylinder 34' is of double-acting type and is interposed in a valve regulated, fluid pressure conduit system 31. Such conduit system is controlled from the tractor and serves as the medium whereby the power cylinder .34 can be caused to extend or contract selectively and at the will of the tractor operator;

The arrangement of parts is such that the link 29 offers greater resistance to forward swingingv motionthan the resistance to rearward swinging motion offered by the central radial lever arm 28.

Consequently, upon extension of the power cylinder 34, the central radial lever arm 28 is first to move, and swings rearwardly, swinging the radial lever arms 26 in'a corresponding direction, which causes the front apron 20 to be raised.

Dependent upon the degree of extension of the power cylinder 34 the frontapron 25 can beadjusted vertically to any point, between fully closed and fully open positions, during loading of the scraper, which loading is accomplished in the usual manner, with the bowl lowered and the blade l2 in ground engagement.

It is thus evident that the front apron 2il'can be adjusted in its working position by the power cylinder 34 Without any motion being imparted to'the rear endgate l4.

Whenit is desired to unload the scraperyi. e. to dump a load fromthe bowl I over the blade I 2' by forward swinging of the rear endgate Hi from its normal position, as in Fig. 3, to its advanced or dumping position, as inFig. 4, the the power cylinder 34 is caused to extend first sufficient to raise the front apron 29 to its full open position, as in Fig. 3', at which time a stop 38 which radiates from-the cross shaft21 abuts the main cross beam I9 ontop thereof. This prevents further rotation of such cross beam, and then with continued extension of the power cylinder 34 the link 29 isswung forwardly, and through the medium of the connector link 3i swings the rear endgate [4 between its normal load carrying position, as in Fig. 3, to load dumping' position, as in Fig. l.

While the described. control mechanism is rela- 'tively simple in its structure, it functions most effectively toward the attainment of selective and '4 sequential control of the front apron 20 and rear endgate 14.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention, as set forth herein.

While this specification set 'sforth in detail the present and preferred constructiono'f the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Ea'ving thus described the invention, the following is claimed as new and useful and upon which Letters Patent are desired:

1. In an. earth working scraper having a bowl including a longitudinally movable rear endgate and a vertically adjustable front apron cooperating with the bowl; a control mechanism for the rear endgate: and front apron comprising separate actuating connections therefor, the connections for the rear endgate including a link pivotally mounted. re'arwardly of the bowl for swing ing in a forward longitudinal direction, the com necticns for the front apron including a, cross shaft mounted adjacent the rear end of thebowl and having a dependent radial lever arm: for swinging in a rearward longitudinal direction, the link havinggreater resistance to forward motion than the lever arm to rearward motion; and a fluid pressure power cylinder connected between said link and lever arm. r a

2. In an earth working scraper having a bowl including a longitudinally movable'rear endgate and a vertically adjustable front apron cooperating with the bowl; a control mechanism for the rear endgate and front apron com-prising'sep arate actuating connections therefor, the connections for the rear endgate including a link pivotally mounted rearwardly of the bowl for swinging in a forward longitudinal direction, the connections for the front apron including across shaft mounted adjacent the rear end of the bowl and having a dependent radial lever arm for swinging in a rearward longitudinal direction, the

ling having greater resistance to forward motion than the lever arm to rearward motion, a fluid pressure power cylinder connected between said link and lever arm, a stop radiating from the shaft, and an abutment fixed with the scraper which the stop engages after predetermined rotation of the shaft in a direction swinging the lever arms rearwardly.

3. In an earth working scaper having a bowl including a longitudinally movable rear endgate and a vertically adjustable front apron cooperating with the bowl; a control mechanism for the rear endgate and front apron comprising a cross shaft journaled on the. scraper adjacent the rear end of the bowl, radial lever arms depending from opposite ends of the cross shaft, actuating connections 'between said lever arms and the front apron adapted to raise the latter when said lever arms swing rearward, a thirdradial lever arm depending from the cross shaft intermediate its ends and rearward of the rear endgate, a pivotally mounted longitudinally swingable link depending from the frame structure back of the rear endgataa connection between the link and rear endgate, and a fluid pressure power cylinder coupled between said third lever arm and the link, the-link having greater resistance to forward motion than said third lever arm to rearward motion.

4. In an earth working scaper having'a'b'o'wl 5 including a longitudinally movable rear endgate and a vertically adjustable front apron cooperating with the bowl; a control mechanism for the rear endgate and front apron comprising a cross shaft journaled on the scraper adjacent the rear end of the bowl, radial lever arms depending from opposite ends of the cross shaft, actuating connections between said lever arms and the front apron adapted to raise the latter when said lever arms swing rearward, a third radial lever arm depending from the cross shaft intermediate its ends and rearward of the rear endgate, a cross beam in the scraper directly ahead of the cross shaft, a stop radiating from the cross shaft in position to engage the cross beam after predetermined rotation of said shaft in a direction to swing the first named lever arms rearward, a link pivoted to and depending from the cross beam, a connection between the link and rear endgate, and a fluid pressure power cylinder coupled between said third lever arm and the link; the link having greater resistance to forward motion than said third lever arm to rearward motion.

, DONALD E. MURRAY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,253,808 Petrucci Aug. 26, 1941 2,406,826 French et a1. Sept. 3, 1946 2,411,688 Keim et a1 Nov. 26, 1946 

